The present invention relates to a moldable biaxially stretched polyester film having an excellent moldability, flatness and heat resistance.
Conventionally biaxially stretched polyester films have been widely used for a variety of industrial uses because of their excellent mechanical strength and heat resistance. For examples, polyester films have been investigated as a raw or ancillary material for vacuum forming, air-pressure forming, overhanging forming, cold forming, injection molding, in-molding, embossing, etc., and also have been investigated to use them a film for molding-transferring, a film for molding container, an insulating film, a packaging film, a decorative film, etc.
However, biaxially stretched polyester films are inferior in moldability in general to vinyl chloride resins, and therefore, the films have been difficult to be applied for the above uses. And, in particular, improving the moldability of biaxially stretched polyester film have been desired in using the film as a base film for molding-transferring or molding container.